different file types in windows disk cleanup tool

Include:
Temporary Setup Files - These files should no longer be needed. They were originally created by a Setup program that is no longer running.

Downloaded Program Files - Downloaded program files are ActiveX controls and Java programs that are downloaded automatically from the Internet when you view certain pages. They are temporarily stored in the Downloaded Program Files folder on your hard disk. This option includes a View Files button that allows you to see the files that would be removed. The button opens the C:\Winnt\Downloaded Program Files folder.

Temporary Internet Files - The Temporary Internet Files folder contains Web pages that are stored on your hard disk for quick viewing. Your personalized settings for Web pages are left intact. This option includes a View Files button that displays the files to be deleted. The button opens the C:\Documents and Settings\Username\Local Settings\Temporary Internet Files\Content.IE5 folder.

Old Chkdsk Files - When Chkdsk checks your disk for errors, it might save lost file fragments as files in your disk's root folder. These files are unnecessary and can be removed.

Recycle Bin - The Recycle Bin contains files you have deleted from your computer. These files are not permanently removed until you empty the Recycle Bin. This option includes a View Files button that opens the Recycle Bin.

Temporary Files - Programs sometimes store temporary information in a Temp folder. Before a program quits, it usually deletes this information. You can safely delete temporary files that have not been modified in over a week.

Temporary Offline Files - Temporary offline files are local copies of recently used network files that are automatically cached for you so that you can use them when you are disconnected from the network. There is a View Files button that opens the Offline Files folder.

Offline Files - Temporary files are local copies of network files that you specifically made available offline so that you can use them when you are disconnected from the network. There is a View Files button that opens the Offline Files folder.

Compress Old Files - Windows can compress files that you have not used in a while. Compressing the files saves disk space while still enabling you to use them. No files are deleted. Because files are compressed at different rates, the displayed amount of disk space you will gain is approximate. There is an Options button that you can use to specify the number of days to wait before an unused file is compressed.

Catalog Files for the Content Indexer - The Indexing service speeds up and improves file searches by maintaining an index of the files on the disk. These files are left over from a previous indexing operation and can be deleted safely.

Office Setup Files - The Office Setup Files are used by Microsoft Office during program updates. If you visit http://office.microsoft.com/en-us/officeupdate you can check for these free program updates to Microsoft Office by clicking the "Check for Updates" link.Your computer may need the Office Setup Files to help apply those updates. If you don't have the Office Setup Files on your PC, the update process will ask you for your Microsoft Office install disks. The Office Setup Files are used to make updates easier. Without them you often have to dig up the install CDs when updating.Unless you’re unusually low on disk space, I always recommend you leave the Office Setup Files on your computer. The increased convenience is worth it.